Feeding device for rock drills



y 1945- I P. A. LINCOLN 2,379,811

FEEDING DEVICE FOR ROCK DRILLS Filed Jan. 25, 1944 59 47 Ffg-r? HIS ATTORNEY.

' portions .of the V drilling mechanism.

I, Patented July 3, 1945 "FEEDI'NGDEVICE FOR'RO'CK DRILLS liBaiul ;A. .a'Lincoln, iBloomsburyj 4.1., :as'signor "to iIngersolleBiand Company, rNcw York, N. Y., a-

-oorpration=o NewJersey 'Applicat ionJ-anuary 25, 194-4, SeriaPNm' 519,601 (Cl.:121--91) v Claims.

This invention relates to'rock drillingmech- 'anism, and ,more-particularly'to a feeding device for advancing a rock drilltowardand retracting it from the work. v "The invention isintendedifor use inconnection with rock'drillihg Vmechanism comprising a motor for effecting feeding movement and in the operation of which drillingimechanism only a comparatively smallportionof the operators time 'isactually required "to control and super-,-

vise the operation thereoffjNormally, itis merebeginning of a cutlan'dto cause itto operate in 'a reverse direction at the endpf a run of drilling "for returning the rock drill to its istartingipo sition.

.In the meantime the operator ispfreeto per- 'form other dutiesarising in connection with the work. It, therefore, happensat times that; he

is occupiedwithasuch matters iattthetime the tly'nccessaryfito start the feeding motor at the rock drill reaches the rearmostilimiting position on the member supportingi t. ,Insuchcasathe rock drill is often forced into such tight locking engagement with other ,parts of the drilling mechanism that it"isimpossible to again start rock drill ,uponits guidepbefore thejrock drill may .be drawninto a positionto cause. jamming of therotative parts of the feeding mechanism; ,Qther objects, will be in .part obviouseand .in Dartpointed .out hereinafter. M l

In the drawing accom n ing this specification and. in which ,similar reference numerals refer to similarzpa'rts, j w

Figure ,1 .isia longitudinal,side elevation of a rock drilling .mechanism having .the invention hpbliedthereto, i t l t [Figure 2 [is anenlarged longitudinal view of the feeding device lof the, drilling, mechanism, partly broken away, and l t Igures ,3 and A are .ztrans verse views .taken through Figure 2 on thelines .3 3 and 4-4, =respectively.

[Referring more particularly ito the drawing mitted=frcm the] motor 23 to the rock drill by a feed screw 24.

The shellflzmay be of awellknowmtype haW ing a conet25 for cooperation with a suitable clamping. device (not shown) whereby the-drilling mechanism maybe secured to astationary mounting. ;In the opposed inner surfaces of the "shell are longitudinally extending grooves screwid and locked inposition seating,against'thelugzll. j H a 'IIhe motor '23 which is attached to the, rear end of thevshell I22 byhdlts f32is of thefluid 'actuatedrotary vane type. "'It comprisesa Ga ing 133 which tconsis'ts of a plurality got sections that rare clamped together in the correct assembled. relationshipiby the bolts 3 2 K Withinthe V casing ,33 v is a xchaniber 3,4 nfor the accominoda -v tion of..a,piston orrotorLfifij-thatiis disposed centricallywithin the \Jchamber andqh plurality of radially extending Slots 1.3.6 containing vanes ,3! against which pressure fluid] acts for rotating .theroton t The motor,2351slofflthetreversibletypelandfthe directionof rotationthe'reof is controlled by a valve 38 rotatable inavalve chamber {39 adjacent I the chamber 34, JIhe valve 138 Q has ,a J bore stance port 4| leading therefrom .-to,register with,passages .42 and .4, 3 ileadingito opposite. sides vof the ,point I of minimum ,clearance between Q the wall of thevchamlrier 3.4 andflthe peripheral sur face oftthe, rotor. The; passages ,42 I and 43 serve tolconveyvpressure 'fluidinto the motor for driv ing it andlasan outltlfor .airtfrom the inactive sidetof ,the1motorchamber v Q ,In order, therefore, to ,peermiththeeslcape ,of air from the, spaces lbetwe'enl lthe vanes 31 througha passage 42 v or 43. aftenSaid ,vanes have passed the main atmospheric exhaust portgfiq of the :motor chamber, the valve "38 provided in its outer surface with longitudinally extend:- ing grooves tand46 to register, respectively, with the passages 42 and 43. The grooves 45 and AGtarelQcated in diametricallylopposed portions of .the valve andtserve, intgiven positions of the valve, to establish communication be-v tween the passages 42, 43 and atmospheric vents Aland 48, respectively. 1 t

=One atmosphericvent, that designated 48 .in the 1 present instance, leads; directly from theval ve chamber -39to the atmosphere, and .the 'ventJll extends'through the casing .33 to a: pointlin the forwardtportion thereof. Thus, by the arr an gement described, air entrapped betweem the vanes on the inactive sideof the-motor may escape V through a passage 42 or 43, a groove 45 or 46 and a vent 41 or 48 depending upon tion of rotation of the rotor 35.

In the arrangement shown the vent 41 opens into a bore 49 in the forward portion of the casing 33 and into which the rearward end of the feed screw 24 extends. The bore 49 is of larger diameter than the feed screw so that the portion of the bore 49 into which the vent 41 opens serves, in effect, as a chamber ll'to receive the air expelled from theinactive side of the chamber 34. A port 5| in the casing 33 affords communication between the chamber 50 and the atmosphere.

The inner end of the chamber 50 may, as shown, be defined by a bushing 52 serving as a bearing annular extension 56 that projects from the forward endof the casing 33 into the path of the feed nut so that when the rock drill approaches.

the motor casing the feed nut 30 will abut the annular extension 56 and slide the valve .53 rearwardly across the outlet 54. The extension 56 is of, suitable length so that the valve 53 maybe shifted into this position by the rock drill before the stationary parts of the motor and the rock drill. willcome into engagement with eaehother.

Any suitable means may be provided for transrnitting driving movement from the motor'to the feed screw 24. That illustrated is of known type. It comprises an internal gear 51 that is rotatable on the wall of a chamber 58 in the casing 33. The teeth of the internal gear are in splined en- -gagement with ribs 59 on the periphery of a flange 60 on the rearward end of the feed screw 24. The

" flange 60 occupies the forward portion of the internal'gear and the rearward portions of the teeth of the internalgearlintermesh with those of a pinion 6| carried by a shaft 62 in the rotor andinterlockingly connected thereto by a key 63. The feed screw 24 is held against longitudinal movement relatively'to the motorand a thrust button 64 is aocordingly'arranged in a plate member 65 located between the chambers34 and 58 to serve as an abutment for therearward end of the feed screw 24 toprevent movement thereof The valve 53, is normally held in posithe direc- .for the terminal portion of the feed screw 24,

thus place the right hand side of the chamber 34,

as shown in Figure 3 of the drawing; in communication with the atmosphere. 1

After the run of drilling'has been completed the valve 38 is rotated to another controlling position to place the port 4| in communication the outlet 54. Thereafter, the air spilled from the spaces be- .tween the vanes 31 of the inactive side of the rotor into the passage 42 and associated passages willbe compressed, and when the presssure thereof reaches a value approximately equivalent, to the driving pressure on the active side of the rotor the motor will come to rest.v This. will take place before the feed nut may bedriven into engagement with the casing part of the motor and all the rotative parts of [the feeding mechanism will,

in the direction of the motor. Movement of the feed screw in the opposite direction is prevented by the bushing 52 the inner end of which abuts the adjacent, end of the flange 60. As a preferred arrangement the conduit 6t serving to convey pressure fluid to the motor for driving it is also connected to the member 65 which has a passage 61 to afford constant communication between the conduit 66 and the bore 40 of the valve 38.

In the operation of the device and with the valve 38 positioned to place the port 4 I in registry withthe passage 42 the rotor 35 and, therefore, the feed screw 24 will rotate in a clockwise direction, as Figures 1 and 2 are viewed from the left hand side of the drawing. This movement of the feed screw will cause the rock drill 2| to slide forwardly along the shell 22 to maintain the rock drill in the correct driving relationship with the working implement 28. In this position of the valve the groove 46 will be in position to com-. municate the passage 43 with the vent 48 and therefore, be entirely freeto again drive the rock drill forwardly along the guide shell.

vI claim: l

1. In a feeding device, the combination of a guide member and a rock drill slidablethereon, a fluid actuated motor having an inlet passage forpressure fluid and an outlet, means for transmitting movement from the motor to the rock drill to slide the rockdrill along the guide member, a valve for controlling the outlet and being guided only by the motor, andmeans onthe rock drill to engage the valve in only a rearward position of the .rocl drill on the guide'for moving the valve into position for closing the outlet to entrap fluid in the motor for stalling saidmotor.

2. In .a feeding device, thecombination of a uide member and a rock drill slidable thereon, a

fluid actuated motor having an inlet passage for pressure fluid and an outlet, means forconnecting the motor to the, guide member, means for transmitting movement from the 'rnotorto the rock drill for sliding'theroek drill along the guide member, a valve tolcontrol the outlet guided only by the motor and being normally positioned to uncovertheoutlet, and means on the rock drill toengage the valvein only a rearward position of the'rock drill on the. guide. to move the valve into position for closing'the outlet to entrap fluid in the motor for stalling the motor.

, 3. In a feeding device,.the combination of a guide member and a rock drill slidable thereon,

a fluid actuated rotary motor having'an inlet passage for pressure fluid and an outlet, means for connecting the motor to the guide member, I

a feed screw for transmitting movement'fr'om the motor to the rock drill to slide the rock 'drill along the guide member, means for preventing endwise movement of the feed screw with respect to the motor, a'reciprocatory valve to controlthe outlet and encircling the feed screw in spaced relation therewith, a spring to normally holdthe valve in position for uncovering. the outlet, and means on the rock drill to slide the valve; into position for closing the outlet to entrap fluid in the motorfor stalling the'inotor.

PAUL A. LINCOLN/Q 

